sql**如下：
select
count
(r.id)
as weight ,r.
*,m.
*from room r left
join meeting m on m.room_id =r.id
where r.tenant_id =
1and r.is_del =
0and
(m.organizer_id =
7or m.organizer_id is
null
)group
by r.id,r.name
sql語句1：
select
count
(r.id)
as weight ,r.
*,m.
*from room r left
join meeting m on m.room_id =r.id
where r.tenant_id =
1and r.is_del =
0group
by r.id,r.name
sql語句2：
select
count
(r.id)
as weight ,r.
*,m.
*from room r left
join meeting m on m.room_id =r.id
where r.tenant_id =
1and r.is_del =
0and
(m.organizer_id =
7or m.organizer_id is
null
)group
by r.id,r.name
即：
m.organizer_id =
7or m.organizer_id is
null
這裡看到這個查詢條件加在where後面，現在把他提前，放到on後where前，即：
select
count
(r.id)
as weight ,r.
*,m.
*from room r left
join meeting m on m.room_id =r.id and
(m.organizer_id =
7or m.organizer_id is
null
)where r.tenant_id =
1and r.is_del =
0group
by r.id,r.name
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